Corner screed bead



1965 A. F. ARNOLD 3,201,908

CORNER SCREED BEAD Filed Oct. 6. 1961 2 Sheets-Sheet 1 INVENTOR.

ALFRED F. ARNOLD y I? w ATTOm Aug. 24, 1965 A. F. ARNOLD 3,2Mfi68 CORNER SCREED BEAD Filed OCT,- 6. 1961 2 Sheets-Sheet 2 mum-r... C t

INVENTOR.

' ALFRED F. ARNOLD ATTORNEY United States Patent C) 3,201,968 (IGRNER SCREED BEAD Alfred F. Arnold, 1296 Bermuda St, Clearwater, Fla. Filed Get. 6, 1961, Ser. No. 143,438 2 Claims. (til. 52-255) This invention relates to improvements in construction members of the type known as corner screed beads for use in forming corners in plaster work at the junct1ons of walls and around window and door recesses, for example. More particularly, the invention is directed to improvements in that kind of corner screed bead which is secured to the lath, studding, rough plaster, or dry wall where a corner is to be formed, and which is substantially buried by the application of a finish coat of plaster,

the corner screed head serving as a guide and anchor for the finish coat, thereby assuring corners or edges which are smooth and regular.

' It is one object of this invention to provide an angular corner screed bead or strip, which is preferably formed of a resiliently flexible plastic material, and comprises first and second elongated flanges joined by a bead of circular cross section and extending normal to one another so as to permit installation to either an inside or an outside corner with the bead serving as a guide for the application of finish plaster in either instance.

Another object of this invention is the provision of such a corner screed bead wherein the flanges have a plurality of openings defined therein and surrounded by flat areas of the flange, through which openings finish plaster may flow and adhere to the rough plaster, lath, or dry wall base, and wherein the flanges are provided with a pattern of projections or raised embossments on the surfaces thereof and between the openings therein, the projections or embossments, in the form of ribs for example, serving to space the flanges from the rough plaster or other base Q material so that finish plaster can flow behind the flat imperforate portions of the flanges to make a more com plete bond with the base material.

As another object this invention aims to provide an improved corner screed bead or strip of the above men tioned character for use in plastering corners and the like, and which corner screed bead may be readily cut with a hand shears to form mitered joints at intersections such as occur around window or door recesses, the pattern of projections or embossments comprising raised ribs on the surfaces of the flanges, the ribs being disposed so as to define 45 angles with respect to the edges of the flanges, and each rib being disposed at right angles with each rib adjacent thereto, whereby the ribs provide a visual guide for quickly and easily making accurate 45 miter cuts in either direction and at any place along the length of the corner screed bead without the use of any angle measuring instrument or the necessity of scribing. In one preferred form, the pattern comprises a series of crossed ribs.

Other objects and advantages of the corner screed beads embodying this invention will become apparent from the following detailed description of a presently preferred embodiment taken in conjunction with the accompanying sheet of drawings forming a part of this specification, and in which FIG. 1 is an elevational view of one side of a corner screed bead embodying the present invention, with a portion broken out thereof;

FIG. 2 is an enlarged sectional view taken along line 22 of FIG. 1 with parts broken out;

' FIG. 3 is an elevational view of the corner screed head of FIG. 1 shown installed on an outside corner and partially covered with finish plaster;

FIG. 4 is a sectional view taken along line 44 of FIG. 3;

32% l ,90 Patented Aug. 24, 1965 FIG. 5 is an elevational view similar to FIG. 3 but showing an inside corner;

FIG. 6 is a sectional view taken along line 66 of FIG. 5;

:FIG. 7 is an enlarged fragmentary view of a portion of FIG. 6;

FIG. 8 is an elevational view of a corner screed head which has been cut in preparation for forming a mitered joint; and

FIG. 9 is an elevational view of a mitered joint formed by corner screed beads of this invention.

In the form of the invention illustrated in the drawings, there is provided an angular corner screed head 10 which is adapted to be used in forming smooth and regular plaster corners. Corner screed head 10, which is preferably formed from a resiliently flexible plastic material such as polystyrene or polyvinyl, comprises a solid head 12 of generally circular cross section, and first and second elongated flanges 13 and 14 which are formed integrally with bead 12 and extend radially therefrom at right angles to one another so that the flanges may be regarded as having inside and outside surfaces, as is best illustrated in FIG. 2.

The flanges 13 and 14 each comprise a flat web portion 16 the thickness of which is substantially less than the diameter of bead 12 so that the bead presents an exposed convex surface thereof between the inside surfaces of the flanges. A plurality of openings 18 extend through web portions 16 or" flanges 13 and 14, and are surrounded by flat surface areas 19 on the outside of the flanges and the flat surface areas 20 on the inside thereof. A pattern of projections or raised embossments presented on the inside and outside surfaces of each of the flanges 13 and 14, and in the example shown the projections or embossments comprise a series of ribs 21 and a series of ribs 22 crossing ribs 21.

The ribs 21 and 22 preferably terminate short of the free edges of flanges 13 and 14 and short of the junction of the flanges with head 12. The ribs 21 are parallel to one another and are disposed to define acute angles of 45 with the free edges of the flanges and with the junction of the flanges with the head 12 as indicated in FIG. 1. Ribs 22 cross ribs 21 at right angles thereto and likewise form angles of 45 with the edges of the flanges on which they are embossed.

The ribs 21 and 22 are of such a size or height above the surface of webs 1d that the apexes of the ribs on the outside surfaces of the flanges lie in planes 24 which are tangential to the surface of head 12, while the apexes of the ribs on the inner surfaces of the flanges lie in planes 26 which converge at a line passing through points 27 on the exposed convex surface of head 12 between the flanges. The openings 18 are conveniently arranged in geometrical groups between the ribs as shown, although they may be randomly disposed therebetween if desired. It will be noted from FIGS. 1 and 2, that the side walls 18a of openings 13 are formed at an angle to a line 2 3extending normally to the web portion 16, for a purpose which will become apparent as the description proceeds.

Although the corner screed bead Jill may be made in other sizes and other dimensions, as well as of other resiliently flexible plastic than polystyrene and polyvinyl, I have found that when formed with a bead 12 having a diameter of of an inch, flanges 13 and 14 of 2 inches in breadth, web portions 16 of A inch thickness, openings of inch in diameter, and ribs standing inch above the surfaces of the webs provide the most satisfactory results in the majority of applications thereof. The corner screed beads 10 are supplied in convenient lengths such as eight or ten feet and may be readily cut with hand shears or scissors to form shorter lengths, miter joints, and

the like in amanner which will later be more fully de scribed.

Corner screed beads embodying this inventionrnay be I used to advantage in forming either' inside or outside corners, as well as three-way corners or intersections corner, the corner screed bead'10 is pressed by hand over the corner formed by abase material such'as rough plaster, lath, dry wall, or the like, the base material being.

betweenthe inside surfaces 20 of the webs 16 and the rough plaster. The corner-screed bead is securedin this .shown as rough plaster-30' in this instance. The ribs 21 and 22 engage the rough plaster and assure a space position by the use of smallnails, staples, or the like,

which are preferably driven by an automatic hand gu n;

A coat of finish plaster 35 is then applied by the plasterer so as to substantially bury the'corner screed bead 10 while forcing a quantity of finish plaster through openings 13 and in thespace provided by ribs 21' and 22,

behind the flat imperforate areas of webs 16 between holes 18, so that a substantial quantity of finish plasteris disposed as at 35a between the flanges and the rough plaster to form a strong adhering bond therewith.- The exposed surface of head 12 providesa smooth, rigid guide against which the plasterer may cause his trowel to travel as he forms alayer of finish plaster over the exposed surfaces of flanges 13 and 14, while the exposed ribs 21 and 22 thereon serve as a guide for the trowel assuring a a I uniform layer bof finish plaster over the, exterior of the web portions 16;

The angle of the side walls 18a of the openings 18 7 provides a locking effect in one direction to prevent any likelihood of finish plaster layer 35b from pulling away from the corner screed head 10, and provides a similar locking effect in the other direction'to-prevent the'corner strip 10 from pulling away from the layer 35a of finish plaster. It will be recognized, therefore, that the com pleted construction will be uniform and regular in appearance byreason of the guiding characteristics of the head 12 and ribs 21, 22, and that the construction. will remain rigid and secure because of the layer 35a of finish plaster assured by the spacing action of ribs 21 and 22 against rough plaster 30 and because of the locking action of the angularly formed openings 18'. a

A similar corner construction is illustrated in,FIGS. 5, 6 and 7 in which the corner screed bead 10 has been applied to an inside corneror wall intersection, the steps in the construction being the same as those described with reference to FIG. 4 as will be readily understood by those skilled in the art to which the invention pertains;

In many instances it is. desirable to join two comer screed beads 10 with mitered jointsat intersections of more than two surfaces, such as occur 'at the corner formed by two walls and a ceiling, around window or door recesses, hallway entrances,- and' the like. I Such rnitered I prising joints are easily and accurately made when using the corner strip embodying this invention by utilizingthe ribs 21 and 22 as guides along which the workmen may;

cut the corner screed bead with simple handsh ear' or' I scissors so as to form a 45 mitered end surface 40. on the f is illustrated in FIG. 9 wherein a corner scre ed bead 1t)" has a mitered end surface 40 abutting a similar surface 46 of another corner screed head 10.

punches and dies or, by extrusion forming of the general angular shape of the corner screed bead followed 'by forming of the openings 18 and rib-s 21, 22 by continuously operating rotary dies. In addition, the plastic material The corner screed beads 10 may be produced by suitable colored plasteras issometimes used. Because of the pleasing appearanceprovided by the embossed pattern, and because the corner screed beads 10 mayvbei'pigmerited, other. usesmaybe found therefor, for example as decorative molding pieces. I 1

Although the invention has been .describedin' considerable detai l'with reference to a specific example-of corner screed bead embodying the invention, it will be understood thatthe, invention isfnot limited thereto, but rather the invention'incl'udes all' those modifications, adaptations,

and uses as are claims hereof.

Having thus described my invention, I claim: 1 I 1. "A corner screed head for use informing inside and outside plaster corners, said corner screed bead being formed of resiliently flexible plastic material and comprising:"- 1 I V (a) a solid head of circular cross section, (b) first and second elongated flanges joined by said I solid bead and each having a freeedge, said flanges extending radially 'from said solid head at right angles to one'another so thatthe flanges have inside andout'side surfaces, (e) I said flanges having flat web portions and a plurality ofspaced ribs projecting above said-flat'web' portions I on the inside andoutside surfaces of said flanges, (d) said web portions beingof a thickness 'which'is substantially lessjthan the diameter of said solid' head so that said solid bead presents an exposed convex surface thereofbetween said flanges, said web portions'having a plurality of openings therethrough between said ribs,

reasonably embraced by the scope of the (e) said ribs being'disposed at angles of 45 to said I solid bead and. to said'free edges of said flanges, the spaces of theribs on the outside surfaces of said I 'flanges'lying in planes which are tangent to said solid bead, and the apexes of the ribson the. inside surfaces ofsaid flanges lying in planes which converge at a line lying in said exposed convex surface of said solid bead between said flanges. 5 2. A corner screed bead for usein forming inside and outside plaster corners, said'corner'screed bead being formed of resiliently flexible plastic material and corn- (a) asolid head of circular cross section, (b) first and sjecondelongated flanges joined by said solid bead and each having a free edge, said flanges eXtending radiaIIy from said solid head at right angles to one another so that the flanges have inside "and outside surfaces, I v (c) said flanges having flat web portions and a plurality of spaced ribs projecting above said flat web portions on the inside and outside surfaces of said flanges, I I (d), said web portions being of athickness which is substantially less than the diameter of said solid bead (so that said solid bead presents an exposed convex surface thereof between said flanges, said web portions having a plurality of openings therethrough between said ribs,

(e) said ribs being disposed at angles of 45- to said solid bead and to said free edges of said flanges, the .a'pexes' of the ribs on the outside surfaces of said flanges lying in planes which, are tangent to said solid bead, and the apexes of the ribs on the inside surfaces of said flanges lying in planes which converge at a line' lying in said exposed f convex surface. of said j solid bead between said flanges, (f) said ribs terminating shortzof said solid beadand of Isaidfree edges, vand the ribs on each ofsaid surfaces of the flanges comprising a series of parallel 5 6 ribs each crossing a rib of another series of parallel 2,927,339 3/60 Grunwald 20-74 X ribs at right angles thereto. 2,953,835 9/60 Armstrong et al. 20-74 X References Cited by the Examiner 3O90087 5/63 Mluer 50 194 UNITED STATES PATENTS 5 FOREIGN PATENTS ,3 85 Harsha 20*74 646,268 11/50 Great Britain. 694,111 2/02 Schratweiser 50503 715,045 9/54 Great Britain. 1,308,773 7/19 Clark 50-46 1,248,986 11/60 France. 2,012,203 8/35 Peterson 50-165 2,101,883 12/37 Warner 94-18.2 10 HENRY C. SUTHERLAND, Primary Examiner. 2,189,216 2/40 Mathias 50165 2 7 553 /54 Dunlap 50 171 WILLIAM MUSHAKE, Exammer- 

1. A CORNER SCREED BEAD FOR USE IN FORMING INSIDE AND OUTSIDE PLASTER CORNERS, SAID CORNER SCREED BEAD BEING FORMED OF RESILIENTLY FLEXIBLE PLASTIC MATERIAL AND COMPRISING: (A) A SOLID BEAD OF CIRCULAR CROSS SECTION, (B) FIRSFT AND SECOND ELONGATED FLANGES JOINED BY SAID SOLID BEAD AND EACH HAVING A FREE EDGE, SAID FLANGES EXTENDING RADIALLY FROM SAID SOLID BEAD AT RIGHT ANGLES TO ONE ANOTHER SO THAT THE FLANGES HAVE INSIDE AND OUTSIDE SURFACES, (C) SAID FLANGES HAVING FLAT WEB PORTIONS AND A PLURALITY OF SPACED RIBS PROJECTING ABOVE SAID FLAT WEB PORTIONS ON THE INSIDE AND OUTSIDE SURFACES OF SAID FLANGES, (D) SAID WEB PORTIONS BEING OF A THICKNESS WHICH IS SUBSTANTIALLY LESS THAN THE DIAMETER OF SAID SOLID BEAD SO THAT SAID SOLID BEAD PRESENTS AN EXPOSED CONVEX TIONS HAVING A PLURALITY OF OPENINGS THERETHROUGH TIONS HAVING A PLURALITY OF OPENINGS THERETHROUGH BETWEEN SAID RIBS, (E) SAID RIBS BEING DISPOSED AT ANGLES OF 45* TO SAID SOLID BEAD AND TO SAID FREE EDGES OF SAID FLANGES, THE APEXES OF THE RIBS ON THE OUTSIDE SURFACES OF SAID FLANGES LYING IN PLANES WHICH ARE TANGENT TO SAID SOLID BEAD, AND THE APEXES OF THE RIBS ON THE INSIDE SURFACES OF SAID FLANGES LYING IN PLANES WHICH CONVERGE AT A LINE LYING IN SAID EXPOSED CONVEX SURFACE OF SAID SOLID BEAD BETWEEN SAID FLANGES. 